This invention relates to improvements in the manufacture of fibrous webs.
In the manufacture of fibrous webs by the air-lay principle, care must be taken to ensure uniformity of distribution of fibers on a forming wire. Air-laid fibrous webs have a tendency to undesirable formation of streaks, flocks, and the like.
The following U.S. patents are representative of prior-art efforts directed to overcoming the hereinabove discussed difficulties, and are believed material to the examination of this application:
U.S. Pat. No. 3,644,078 discloses a duct 108 for directing fibers onto an underlying moving distribution screen 109 for feed onto a lower forming wire 115 moving in the same direction. A transversely extending rotatable brush 110 contacts and scatters the fibers through screen 109.
U.S. Pat. No. 2,912,723 discloses a horizontally reciprocating fiber sifting screen 28 disposed above a forming wire screen 25.
U.S. Pat. No. 3,575,749 discloses rakes 34 in contact with a perforated band 28 moving in one direction for defibrating fibers and assisting the fibers therethrough and onto an underlying oppositely moving perforated forming band 21. A stationary screen 41 is positioned intermediate band 28 and forming band 21.
U.S. Pat. No. 2,940,135 discloses brushes 83 radially arranged on a rotor 80, and which urge fibers through an underlying stationary arcuate perforated head 72 onto a lower moving screen 10.
It is a general objective of this invention to provide an improved method for the manufacture of air laid fiber webs.
It is a further objective of the invention to provide an improved method for the manufacture of fiber webs so that the webs are substantially devoid of streaks, flocks, and the like.
It is another objective of the invention to provide improved means for distributing fibrous material onto a forming wire of apparatus for the manufacture of fiber webs.